Fuel-oil burner



W. M. HOFFMAN.

FUEL Ol-L BURNER.

APPLICATlON FILED APR. 13.. 1921.

Patented June 113, 1922.

UNHT

TTTILLIAFI MI HQFFMLAN, OF BUFFALO, NEW YORK, ASSIGNGR- TO GENERAL FUEL APIPAEATUS CQEPOEJLTTON, OF BUFFALO, NEW YORK, A GUBPOBAIION 0F DELA'W FUEL-OIL BURNER.

Original application filed June 7', 1920, Serial No. 387,003. Divided and this application filed. April 13,

7'0 (1 w ham it may concern:

Be it known that 1, WILLIAM Horr- MAN, citizen of the United States, residing at Buffalo, county of Erie, State of New York, have invented a certain new and useful Improvement in Fuel-Oil Burners, and declare the following to be a full, clear, and exact description of the same, such as will enable others skilled in the art to which it pertains to make and use the same, reference being bad to the accompanying drawings, which form a part of this specification.

This application is the result of a division of my'application No. 387,003 filed June 7, 1920 and pertains to a fuel super-heater for use in connection with fuel oil burners similar to the one therein described.

In the original application I show fuel oil burner comprising a hollow combustion chamber open at one end and provided with a jet producing means positioned at the other end adapted to project a vapor jet within the combustion chamber toward the open end thereof. This combustion chamber is composed of porous refractory material and is provided with a partially jacketed casing, the jacket portion of which is adapted to serve as a container for fuel oil. The inner wall of this jacketed portion is perforated to provide fuel oil connecting passageways be tween the interior of the jacketed container and the outer surface of the combustion chamber wall. Fuel oil is thereby supplied to the outer surface of the porous refractory wall of the combustion chamber through which it is permitted to percolate to be burned on the inside thereof. During the passage of the oil throu the wall of the chamber, its temperature is raised until it approaches substantially the point of vola tilization.

In fuel oil burners of the within described class it is highly desirable that the fuel oil be brought to a high temperature before it is introduced into the interior of the combustion chamber to be burned. The fuel oils which these burners are intended to utilize are the cheaper, lower grade oils which contain a large content of tar and asphaltum bases, the more volatile elements of which have been distilled out.

The object of my instant divided application is therefore to provide means, in form Serial No. 461,120%.

of a fuel oil super-heater, through the use of which the temperature. of the fuel will be greatly increased before it is introduced into the combustion chamber. This superheater is of such a character, and so positioned in the fuel feed line, that the liquid fuel must pass therethr ough before it reaches the outer surface of the combustion wall. My super-heater is constructed in the form of a closed coil so positioned as to be heated by the heat developed in the combustion chamber. The liquid fuel passing through the coil will be raised to a high temperature before it is brought to the outer surface of the combustion chamber'wall. The passage of the fuel through the porous wall of the combustion chamber, will, therefore, be facilitated, the heavier asphalt base elements being broken down under the heat, and the temperature and state of volatility of the fuel will be such that when it comes in contact with the oxygen in the interior of the chamber, combustion will readily occur, and be of a high order.

The above and other objects of my inven tion will more fully appear from the following description, appended claims, and accompanying drawings, in which:

Figure 1 is a longitudinal section through my improved burner. I

Figure 2 is a cross section taken on line 2-2 of Figure 1. i

In the drawings, let a indicate a hollow casing open at one end, in the embodiment here shown of cylindrical form. This casing is partially jacketed, as atc, to provide a fuel oil receptacle to which liquid fuel is supplied through a feed pipe (5. The acket is here shown as extending part of the length of the casing and also extending entirely around the casing. It is apparent that the jacketed portion of the casing might be of such size as was found most desirable in the use of the particular grade of oil to be consumed in the burner. It has been found that a jacket extending but part of the length of the casing is sufficient and also it has been found that the jacketed portion need not extend entirely around the casing. A preferable construction being, one, in which the jacketed portion of the casing is provided with communicating passageways 6 through only the upper half thereof, therefore, forc- Cir ing all the oil burned in the combustion chamber to percolate down through. the upper portion thereof.

My combustion chamber is in the form of a hollow porous refractory core 7), adapted to be received within the casing as shown, and being preferably removable to permit of its being cleaned. l he core is formed of material of such a texture as found most suitable for the grade of oil to be burned therein. A core of close texture with a thick wall would increase the length. of time it would take the fuel to percolate thercthrough and therefore serve to such percolating fuel to a higher temperature than would a core constructed of a mi" erial bound together in an open texture with a comparatively thin wall. which would permit the ready passage of fuel thcrethrough.

As shown in my original application above referred to I provide jet producing means positioned at the rear of the casing adapted to project a vapor jet into the interior of the combustion chamber. This jet producing means comprises a nozzle g supplied with vapor through conduit 7L, either with air through conduit k which leads to a convenient source of air supply from which air is furnished unc er pressure the passage of air therethrough being regulated by means of a valve if; or with steam through a separate branch conduit 2', which conduit leads to suitable source of steam supply, the flow of steam therethrough being regulated by means of a valve 6 in the end of the casing opposite the open end and surrounding the j ct producing means is an air draft shutter leading to the at mosphere and by means of which it is possible to regulate the admission of air to the interior of the burner.

My within described invention consists in the provision of the fuel oil pro-heater shown in the form of a closed coil m positioned in front of and in line with the wall of the burner at the mouth thereof. This coil or ring is positioned in the oil feed line leading to the jacketed portion of the combustion chamber casing. The inlet to the coil is indicated as a, and conduit (5 which discharges into the jacketed portion of the casing l a; s from the coil.

Fuel oil is supplied from a suitable source of oil supply not shown. in the drawing, either by gravity feed or under pressure to this super-heater coil or ring.- in the opera tion of the burner there is an intense concentrated heat at the mouth thereof as the operation of my device is somewhat similar to that of a blow torch in that the heat is concentrated rather than as generally occurs dissipated over a large area. The oil, therefore, as it passes through the closed coil m is brought to a high state of temperatture before it reaches the jacketed portion of the combustion chamber. In the use of the various types of fuel for which this burner is intended this becomes particularly desirable in order that the heavy asphaltum base materials carried in the oil be broken down as far as possible before the oil is introduced into the porous wall of the combustion chamber.

li hat I claim is:

1. In a hydrocarbon burner, a combustion chamber in the form of a hollow porous refractory core, a jacketed casing for such core adapted. so that fluid fuel therein contained may pass therefrom to the outer surface of the porous refractory core for percolation therethrougln a vapor jet-producing means positioned at oneend of said core adapted to project a jet of vapor therethrough, means for supplying fuel to such acketed portion of the casing, such means so adapted and so positioned with reference to the combustion chamber that the fluid fuel passing therethrough will be heated before it reaches the j ackct.

2. In a hydrocarbon burner, a combustion chamber in the form of a hollow refractory porous core open at one end, a vapor jet-projecting means positioned at the opposite end adapted to project a j et of vapor therethrough, a jacketed casing for such core, the inner wall of such jacket being perforated to permit of the passage of fluid fuel therethrough to the outer surface of the core, a fuel container positioned in line with and forwardly of said core adapted to be heated by combustion pronuced therein, fuel-coin muuicating means between said fuel container and the jacketed portion of said casing; means for supplying fuel to said container.

2. in a hydrocarbon burner, a combustion chamber comprising a hollow refractory core, the wall of which is adapted for the percolation of fluid fuel therethrough, a jacketed casing for such core adapted to contain fuel oil, such casing perforated to permit the passage of fuel therefrom to the outer surface of the wall of such core means for projecting a vapor jet into one end of said core, a fuel preheater adapted tocontain fuel positioned so as to be heated directly by the products of combustion from said combustion cham ber. communicating means between said super-heater and the jacketed wall of said casing.

i. In a fuel oil burner, in combination, a hollow porous refractory combustion chamber in the interior of which combustion takes place a fuel .oil pre-heater positioned so as to be heated directly by the burning products of combustion emerging from the mouth of the combustion chamber, fuel communicating means between said preeheater and the outer surface of the Wall of the combustion chamber.

5. In a fuel oil burner, in combination with a hollow porous refractory combustion chamber in the interior of which combustion takes place, a main heating chamber for fuel oil, a pre-heater positioned in the fuel feed line leading to the main heating chamber so as to be heated by the heat produced in said combustion chamber.

6. In a fuel oil burner, in combination, a combustion chamber in the form of a hollow porous refractory core open at one end, a fuel feed line adapted to conduct fuel to the outer surface of said combustion chamber wall, a fuel pie-heater positioned in said feed line between the source of fuel supply and the combustion chamber, being so positioned relative the mouth of the combustion chamber as tobe heated by the products of combustion emerging therefrom.

7. In a fuel oil burner, in combination with a hollow combustion chamber open at one end and formed of a porous refractory material so that fuel oil may percolate through the wall to be burned in the interior thereof, a pre-heater coil positioned relative the open end of said chamber so as to be heated by the products of combustion emerging therefrom, communicating means between said pre-heater and said combustion chamber, oil communicating means leading to said pre-heater.

8. In a fuel oil burner, in combination with a hollow porous refractory combustion chamber through the wall of which fuel percolates and in the interior of which combustion takes place, fuel communicating means leading thereto, a fuel preheater through which the fuel must pass before it reaches the combustion chamber and so positioned with respect to the combustion chamber as to be heated by combustion produced therein.

In testimony whereof, l sign this specification.-

WILLIAM M. HOFFMAN. 

